Train control



FIG].

|AS|c July 9, 1929.

F. 1.. DODGSON 1.720.64

TRAIN CONTROL Original Filed Jan. 28, 1924 5 sheets-Sheet l I IN E NTOR.Q 5?- r ATTORNEY H F. L. DODGSON TRAIN CONTROL Juli} 9, 192 9.,

Original Filed Jan. 28; 1924 5 sheets-sheet 2 I N V EN TOA.

F. L. DODGSON TRAIN CONTROL Jul 9, 1923.

5 Sheets-Sheet 3 Original Filed Jan. 28, 1924 MNVENTOR.

July 9, 1929. F. DODGSON TRAIN CONTROL 5 Sheets-Sheet 4 Original FiledJan. 2 8, 1924 i L!!! dill/P3 July-9, 1929. F. L. DODGSON TRAIN CONTROLOriginal Filed Jan. 28, 1924 5 Sheets-Sheet 5 mmm mi m8 Patented July 9,1929.

with; STATES I men Pl @FEQE.

FRANK L. DODGSQ N, OF ROCHESTER, NEXV YORK, ASSIGNOR 'IO GENERAL RAILWAYSIGNAL COMPANY, OF ROCHESTER, NEW YORK.

TRAIN CONTROL.

This invention relates to train control systems, and more particularlyto means for stimulating the vigilance of the engineer and his obedienceto the wayside signals, and for inflicting a penalty if the engineerdoes not manually apply the b 'akes before the speed of the train isexcessive.

In applying automatic train control apparatus to railroads it isconsidered desirable to employ such apparatus as an additional safeguardover that obtainableby a careful, alert and prudent engineer rather thanas a substitute for such engineer. In other words, it is desirable tohave the safety 5 of the train depend on both the automatic traincoi'rtrol apparatus and the engineer, rather than either of these twostanding alone. Also, in applying automatic train control apparatuswhich limits the speed of the train (speed control systems) asdistinguished from a system which stops the train depending alone ontraflic conditions ahead (automatic stop systems) it is found ditiicultto determine what the safe speed at which a train may run at the variouspoints in a block is when the next block in advance is occupied,especially as the blocks are different in length, have different gradesand curves, or the like. lVith the above and other considerations in 3Q)mind it is proposed in accordance with the present invention tojset uparbitrary speed limits at various points in a block which are on theside of safety,'and .are suitable speed limits at which all trains maysafely run,

even though perhpas less than the safe speed limits for certain trains;and to provide means for inflicting a penalty if an automatic brakeapplication occurs because the train passes such a point at a speed inexcess of the arbitrary speedliiuit unless the engineer has anticipatedsuch automatic brake application by initiating a manual application.Another object and feature of the present invention contemplates theprovision of a simple and direct way of determining when an adequatebrake application, such as the usual service application, has beeneffected so far as manual control is concerned, it being desirable toknow if an adequate brake application has 59 been initiated and willtake place, because a certain amount of time transpires between thecompletion of the manual control of a brake application and the brakeapplication itself, this determination or manifestation of the.

. as .ap n opriate in. nnal. control of a brake appli Application filedJanuary 28, 1924, Serial No. 689,020. Renewed July 30, 1927.

cation continuing only so long as the manual control is undisturbed andin time will consummate the brake application. More specifically theproposed apparatus inone form includes a time element device, orclockwork 60 mechanism, which is adapted to suppress the action of apenalizing means providing the engineer has had the usual engineefisbrake valve in the service brake applying position for a predeterminedinterval of time and has not in the meantime returned the brake valve tothe running or release position.

Other objects, purposes and characteristic features of the inventionwill appear as the 7 description thereof progresses.

In describing the invention in detail reference will be made to theaccompanying drawings in which Fig. 1 shows the trackway equipment of atrain control system of the continuous inductive type, a portion of thecar-carried equipment being shown, and speed restricting and trainperformance curves of a particular block to which the present traincontrol apparatus is applied being illustrated;

Fig. 2 illustrates in a diagrammatic and conventional manner thecar-carried equip ment of the train control system just referred to;

Fig. 3 illustrates a car-carried system simi- 5 lar to that shown inFig. 2 (portions thereof being omitted) employing a modified circuitarrangement for the penalty suppressing apparatus;

Fig. 4t illustrates a car-carried system such as shown in Fig. 2employing a modified type of penalty suppressing means which does notinclude a clockwork mechanism;

Fig. 5 illustratesa train control system of the inductive intermediatetime-distance in- 'terval type employing a penalty suppressingarrangement including clockwork mechanism; and

Fig. 6 shows the car-carried apparatus of the system as shown in Fig. 5including a penalty suppressing means similar to that shown in Fig. l.

The specific embodiments of the invention as illustrated in the drawingsconsist of a novel arrangement for penalizing the engineer if he doesnot attend to his duty as ap plied to two distinctive types of systems,

nan'iely, (1.) train control system of the continuof inductive type asillustrat d in Figs. 1, 2, 3 and. at; and (2) an intermittent speed nocontrol system of the time-distance interval type as shown in Figs. 5and (3.

Continuous system.

Traclmoay (LP}P(I/I(ZZ 'L(-t'.-IH Fig. 1 there have been illustrated theusual track rails 1, divided by insulating joints 2 into blocks in theusual manner, only the block I and the adjacent ends of two other blocksH and J being shown. Since the various blocks are the same, like partsof each block have been (.les'ignated bylike reference characters havingdistinctive exponents. Although the train control system embodying thepresent invention may be used in connection with wayside si'gi'ials ofany type, such as semaphore signals, position light signals and colorlight signals, it has for convenience been shown applied to a systememploying sei'naphore signal Z, which have been shown conventionallywithout illustrating any particular form of their well-known controlcircuits and control mechanism.

Each of the blocks is provided with a suitable source of alternatingcurrent energy at the exit end thereof, illustrated as a tracktransformer 3, and a suitable track relay 4 at its entrance end. T hisforms the well-known closed track circuit which needs no furtherdiscussion.

Inaddition to the usual track circuit current flowing in the rails of ablock, there is provided a circuit to permit the flow of alternatingcurrent in the two rails in multiple in 7 the same direction, which forconvenience will hereinafter be referred to as the simplex circuit. Inorder to permit the flow of cur rent in this simplex circuit, includingin multiple the rails of a portion of a block or the rails of the entireblock, three balancing resistances 5, 6 and 7- are bridged across therails at the entrance, at an intermediate point, and at the exit end ofeach block respectively. In order to supply alternating current energyto these two circuits, a transmission line including wires 8 is strungalong the track, the energy for the simplex circuit of each block beingsupplied by the transformer 9.

In order to cause the simplex current to flow in one particulardirection as compared with the direction of How of the loop circuit ortrack circuit current along the entire length ofthe block at one time,and cause it to flow in the opposite direction through a portion of theblock only at other times, front contacts, as 12 and 13 operated by thetrack relay of the block next in advance, as l are provided. Referringto the block I, by looking at the circuits governed by these two frontcontacts 12 and 13 it is readily apparent that if the track relay 4 isin its normal energized condition, current is permitted to flow throughthe two rails in mul tiple in the block I from the middle point of thebalancing resistance 7 to the middle point of the balancing resistance5, and that when this track relay l dcenergized, current will flow in areverse direction from the middle point of the balancing resistance 5through the tworails in multiple to the middle point of the balancingresistance 6 located at an intermediate point in the block. In practicethe constants of these simplex circuits with respect to the constants ofthe loop circuit including the track transformer are so chosen that thephase displacement between these two currents is as large as possible orpractical, so that if these currents are detected by suitable apparatuson the train, that is, amplified and applied to a two element or threeposition relay, this, relay produces a torque in one direction or theother depending on the phase relation between these two currents and inturn on the position of contacts 12 and 13 of the track relay ahead.

Influence co'nmmaicating means-On the vehicle, which has beenconventionally shown by axles l5 and wheels 16, is a pair of loop ortrack circuit influence receiving elements LE, comprising cores 17terminating in pole pieces 18, each having a winding or coil .19thereon. in a manner so that the voltages induced therein, due tocurrents flowing in the opposite direction in the two rails, arecumulative, and these coils are connected to a suitable amplifyingdevicecAL (not shown in detail) which comprises thermionic or vacuumtub'e amplifiers of well-known commercial or special construction. Theoutput lead wiresof this amplifying device AL are connected to thewinding LR of the control re lay B.

At a suitable point on therailwa'y vehicle is a simplex element SIC,which comprises a long core 20 terminating in enlarged pole pieces 21and having a coil 22 thereon for detecting the how of simplex currentin'the two rails in multiple. This coil 22 is connected to the inputside of a similar amplifying device AS which has its output terminalsconnected to the other winding SE of the control relay It. It is thusapy iaren't that, with currents flowing in the loop circuit ahead of thetrain and in the simplex circuit under the train ha ving a certain phasedisplaccn'ient, currents will be supplied by the two amplifying devicesAL and AS of a similar phase relation and will cause the relay It to beoperated in a certain direction, and that, if one of the track currentshas its relative current flow reversed, the control relay It will beoperated The coils 19 are connected in series magnet CSL of a suitablespeed restricting apparatus to be described hereinafter, the currentsfor energizing these two magnets being derived from a suitable source ofenergy such as a battery. The battery is not shown, but B designates aconnection to one terminal, and C a connection to the other terminal.

Train performance speed chara0terist2'0s. Directly over the block I ofthe trackway shown has been illustrated a solid line curve 23 whichshows the permissive speeds at which the train may run without exceedingthe speed limit set up by the car-carried apparatus to be describedhereinafter. It will be noted that this curve has a droopingcharacteristic in the first part of the block I, eontinues as a straightline corresponding to a constant speed for a distance, and then againdroops until it reaches a low constant speed limit of miles per hour.Thefirst droop in the curve is caused by the high cam to be describedhereinafter, and the second droop in the curve is due to the low cam.The particular block I in connection with which these curves have beenshown is assumed to be either va clown-grade block or a block in whichthe braking ability of the train is poor for some other reason, andtherefore requires a longer distance of movement to bring the train to acertain value than the distance in which one or the other of these camsrun from a maximum to a minimum speed posit-ion.

The dot-and-dash line 24 illustrated shows the speeds of the train atdifferent points along the track if the brakes are applied when thetrain enters the block I at a speed of about 65 miles per hour. .It isthus noted that, with the character of block assumed, even though theengineer does apply the brakes upon entering the block I, he will beunable to stay below the permissive speed line set up by the high cam,this being shown by the fact that the dot-and-dash performance curve 24crosses solid permissive speed curve 23 at the point 25. Also, if theengineer releases the brakes when he gets below l0 miles per hour limit,and proceeds at a constant speed until he reaches the point X in theblock, he will not be able to stay below the permissive speed curveenforced by the low cam, even though he applies the brakes when passingthe pointX, as illustrated by the fact that the dotand-dash performancecurve .24; crosses the solid permissive speed curve 23 at the point 26.The continuation of the first droop in the dot-a-nd-dash line 24 hasbeen shown by a dotted line 27 which illustrates the speed at thevarious points in the block that the train assumes if the brakeapplication is continued, that is, shows the brake performance curve fora complete stop from high speed. It should be understood that theparticular speed-distance curves illustrated apply only to theparticular set of conditions which have been assumed in order to bringout certain advantageous features of the present invention, and thatthese curves are notnecessarily characteristic of train performances forall trains in all blocks or portions of the railroad. The speed-distancecurves of permissive speed and train performances are merely typical andare not intended to be accurately shown, being susceptible to'widevariation in practice to conform with the different speed limitsrequired for different kinds of equipmentand varying practices onrailroads.

Oar-carried apparatus 0 f Fig. Z.

Penn/{satire and actual speed 77260]t(l7lx2ih'771-.

Since the high cam and low cam operating mechanisms are substantiallythe same. except to the particular shape of the cam and the speed limitenforced, the high cam and its associated mechanism only has beenillustrated. The influence communicating apparatus for controlling boththe high and the low cam has already been referred to, and is shown in1, the cam starter magnet CSH of this apparatus being shown in Fig. 2.On the vehicle l5 l6 a shaft 30 driven by the wheels of the vehicle in asuitable manner. Qn this shaft 30 is a worm 31 meshing with a worm wheel32 which through reduction gears 33 and 3st drives a pinion 35 pivotallysecured in the bifurcated end of an arm 36 which is pivoted about theaxis of the gear 34-, so that the pinion 35 may be moved into or out ofengagement with a mutilated gear 37 without disturbing its meshedrelation with the gear lhis g'ear 3'? is pinned to a cam shaft 88 havinga cam 39 fixed thereon. The arm 36 is urged upwardly by a compressionspring 4-1, disposed around a guide 4-2, so that if the cam startermagnet CSH is deenergized the pinion 35 is urged upward into meshed relation. with the mutilated gear 37, whereupon movement of the vehiclealong the track gradually turns the cam shaft 38 and its associated cam39. In order to return the shaft 38 back to its normal position in theevent that the cam starting magnet CSH is again energized, a gear sector43, pivoted at 4%, engages a pinion i5 on the cam shaft 38; and thisgear sector 43 is biased to an intermediate position by initiallytensioned springs 4:6.

011 the shaft 30 is mounted a centrifugal speed-responsive device G ofusual and wellknown construction. which comprises a collar 47 pinned tothe shaft 30, another similar but grooved collar 48 slidably mounted onthis shaft, these collars being coupled together by links L9 having aweight 50 at their pivotal junction, and a compression coil spring 51between these collars.

Parallel and preferably adjacentto the 'shaft 38 is a speed shaft 53 towhich is pinned a bifurcated arm 54 engaging the groove in the collar48. Pinned to this shaft 53 a speed arm 55 and a speed cam 56. Anincrease in the speed of the sh aft causes the collar 4:8 to move inresponse to the centrifugal force acting on the weights 50 in oppositionto the spring 51, so that the speed shaft 53 an d speed arm 55 and thespeed cam 56 are moved in a clockwise direction. To the lower and freeend of the speed arm, 55 is pivotally secured one end of a floatinglever 57 which carries a roller at its other end engaging the camsurface oi he cam 39. At an intermediate point on thefloating' lever 57is pivotally secured one end of a link 58 which has its other endpivotally secured to an eccentrically located pin on the sector 59,which sector is pivotally supported on a pin 60. Adjacent the sector 59secured a spring linger ()1 which has a roller 62 pivotally securedthereto which rides on the cam surface of the-sec tor 59. This spring);linger 61 normally cooperates with a stationary linger 63 to control asuitable circuit more clearly described hereinafter. Adjacent to thespeed cam 56 are provided similar contacts 64 and 65 which cooperatewith this cam 56.

By looking at this structure it will be readily understood that thesector 59 will move in a clockwise direction in response to moven'ient'of the cam 39 from its normal position. It will also appear that thissector 59 moves in the same or clockwise direction in responseto anincrease in the speet as indicated by the governor G, so that either anin crease in speed or movement of the cam 49 from its normal positiontends to move the sector 59 in the same direction and eventually allowsthe roller 62to ride into the contracted or reduced portion of thissector, thereby opening the contacts 6163. In other words, after the cam39 moves from its normal position, the speed of the train must becorrespondingly reduced to avoidopening of these contacts. Also. it willbe noted that decreasing the speed of the train to a certain value,assumed to be two miles per hour, causes the cam 56 to close a circuitat the contacts 64; and 65 for reasons more clearly de scribedhereinafter.

Brake apply 510g deoicc.-The present train control system assumes theprovision of means to automatically apply the brakes of the train undercertain conditions of the can carried apparati'ls. In order toaccomplish such a brake application, a brake z'q'i ilying device hasbeen illustrated convention ally by the electro-pneuIna-tic valve EPV.This device EPV may vent the brake pipe directly, may operate a suitableengineer-s brake valve actuating means, or may control a suitablepneumatically operated brake applying device which vent-s the brake pipeto a predetermined eXtent and at a predetermined rate.

Since the applicability of any one of these of the present inventionwill be obvious and requires no specific showing, further description ofthis apparatus is deemed unnecessary.

The usual engineers brake valve has been shown conventionally, and isprovided with a handle 66 and with suitable contact sectors 67, 68 and69 which are adapted to close circuits in various positions of thisvalve as shown by the legends adjacent tothese seg ments in thedrzuvings.

Directly below the engineefls brake valve is found a cut-out cock ordoubleheaded cock in the usual air brake system, which has beenconventionally shown by the cook 70 which is provided with a contactsector 71 which bridges the stationary contacts 7 2 when this valve isopen, for purposes more clearly set forth in connection with theoperation of the system.

Time? or clockwork meohaaism.ln order to suppress the penalty moreclearly referred to hereinafter, it is desirable to close certaincontacts, providing the engineer h had his brake valve in the serviceposition for a certain period of time and has not thereafter moved it toeither the running or the release position, and in order to control sucha contact a suitable clockwork mechanism GM has been shown. Thisclockwork mechanism comln'is'es an escapement including a pallet 7 5having headed screws 76 in opposite ends thereof which may be adjustedto change the moment of inertia of this pallet about its pivot 77, andconsequently the period of oscillation of the pallet. This pallet isoscillated by an escapement wheel 78 which is driven through a geartrain as shown terminating with a. gear-'79 connected to av shaft 80through a ratchet wheel 8]. and a dog 82, said dog being urged intoengagement with said ratchet wheel by a spring 83. On the upper end. ofthe shaft 80 is fixed a projecting arm Set having at its end apiece ofinsulation adapted to engz'l ge and close-contacts and 235 when said armis moved to its extreme position.

Pivotally mounted and loose on this shaft 80 is a gear 86 which mesheswit-h a rack 87 connected to a piston 88 in a cylinder 89. This rack 87and piston 88 are normally held in the extreme right hand position shownby a compression coil spring 90 within the cylinder 89. The shaft 80 isoperatively connected to the gear 86 by aspiral spring: 91 for onedirect-ion of movement, and is directly coupled to the shaft 80 for theother direction of movement of the gear by engagement of the pin 92,which anchors one end of the spring 9l-to the shaft 80, with a pin 93fastened in: the gear 86.

Pressure is adapted to, be applied against the piston 88 by connectingthe cylinder 89 to the main reservoir pressure of the air brake systemby an electrically operated valve EV. This electrically operated. valveEV of usual and Well-known construction and includes two valve members94 and 95 which are adapted to connect this cylinder to at1nosphericpressure or main reservoir pressure respectively, the valve 95 normallybeing closed by the action of the compression coil spring 96. In theupper compartment of this valve EV is an electro-magnot of the usualironclad type, including an armature 97 and a Winding 98. If thiswinding 98 is energized, the valve 94 assumes the closed position andthe valve 95 the open position, and main reservoir pressure flows intothe cylinder 89. The flow of air pressure into the cylinder 89 moves thepiston 88 to the left, thereby moving the pin 93 away from the pin 92,and simultaneously tensioning the spring 91. Under this condition of theapparatus the pallet 7 5 will be rocked back and forth in response tothe torque on the escapement wheel 78 thereby slowly allowing the arm 8%to move in a clockwise direction and close the contacts 85 and 235 aftera certain period of time, which is assumed to be about 6 or 7 seconds.This time interval, for which the clockwork mechanism CM is adjusted, isintended to correspond with the time required to vent the regularequalizing reservoir of the air-brake system through the engineers brakevalve enough to cause a full service brake application, or such otherapplication as the permissive speed limits require. If the electricallyoperated valve EV is again doenergized to allow the pressure to escapefrom cylinder 89, the spring 90 moves the rack 87 toits normal positionand causes the pin 93 to engage the pin 02 and turn the shaft 80 back toits original position, this being permitted through the dog and ratchetengagement be-' tween the gear 7 9 and the shaft 80.

Operation.

Normal clam" 00mZri0n-9.-Under normal clear traffic conditions both thehigh and the low cam-assume their highest speed positionwhichcorresponds to the maximum permissive, speed limit, assumed in thiscase to be miles per hour, as shown by the curve 23 in Fig. 1. Assumingthat the speed of the train' is less than this'value, which it isassumed to be as shown by the positions of the various devices in Fig. 2of the drawings, the electro-pneun' atic valve EPV is energized by astick circuit which may be traced as follows Beginning at the terminal Bof a suitable source of energy, wire 100, contacts (l1 and 63, wire 101,winding of the EPV, wires 102 and 103, front contact 10% of the EPV,wire 105, back to common return 7 wire C. r i p r This circuit maintainsthe valve EPV in its normal inactive position, allowing the 'rain toproceed in accordance with the manner in which it is governed by theengineer.

If the engineer should allow the speed of the train to exceed themaximum limit of 65 miles per hour, the action of the governor G throughthe speed arm 55 causes contacts G1-63 to open, thereby interrupting thestick circuit for the EPV and applying the brakes of the train. lVhenthe speed of the train has been reduced to, say, less than 2 miles'perhour, the contacts 64. and 65 close, thereby closing a pick-up circuitfor the EPV, comprising wire 100, contacts 61 and 63, wire 101, windingof the EPV, wires 102 and 106, contacts 65 and 64:, wire 107, back tocommon return wire C. The completion of this circuit again picks up theEPV and this permits the engineer to release the brakes manually if heso desires. This requirement of bringing the speed down to practically astop after exceeding the maximum speed limit, before the brakes can bereleased, is considered to be a penalty, and is assumed. to make himmore vigilant in the control of the train to avoid such a brakeapplication and penalty.

The penalty above described for exceeding the maximum speed limit isoptional; and if desired, by a rearrangement of the circuits which willbe very evident, this penalty may be omitted so far as the maximum speedlimit is concerned, by making the electro-pneumatic valve EPV non-stickfor clear traffic 2 is moving in the block H in the normal di- I rectionof traffic as indicated by the arrow, and that the block J is occupiedby another train. lVith the block J occupied, the track relay 4 isdeenergized, thereby causing the simplex circuit between the entrance tothe block I and the point X to be reversed. Consequently, when thefollowing train in question enters the block I, the control relay R willswing to the reverse position, thereby deenergizing the high cam startermagnet CSl-l', but maintaining the cam starter magnet CSL energized. Thehigh cam 89 is thus initiated and is gradually rotated in one directionor the other, depending on whether thereby gradually reducing thepermissive speed, as indicated by the curve 23 in liig. 1. If the actualspeed of the train does 'not exceed the permissive speed limits at anypoint, no automatic brake application will take efthe train is runningpilot or tender first,

feet, it being assumed for the present that the permissive speed limitsas indicated by the line 23 are not exceeded.

.Atter thetrain passes by the point X, no simplex current of anycharacter can be detected, and therefore the low cam starting magnet-CSLis also deenergized. This condition of the apparatus causes the low camto be gradually turned to restrict the speed of the train as indicatedin the second droop of the solid line (Fig. 1). It the engineer does notallow the speed of the train to exceed at any point. these permissivespeed limits, no automatic brake application takes eil ect.

Cautioncomiitioa; speed cmcessioe.-The gradually decreasing permissivespeed limits, indicated by the curves .43 and the solid lines in Fig.1,.are produced by movement of the two cams; and since these cams aredriven from the car wheels, the curves of pern'iissive speed set up arethe same for each block or control point on the railroad, whether on anupgrade or on a down-grade; and these pormi. ive speed curves are thesame tor the particular locomotive equipped whet-her running alone orpulling a long or a short train. As previously explained, theresometimes are portions of track where it is not possible ilor all trainsto keep below the permiss ve speed limits at all points in a cautionblock, unless the train is handled and braked in some unusual orpeculiar manner. I

In conformity with the theory of train control on which this inventionis based, it desired. to stin' ulate and enforce vigilance on the partof the engineer in obeying the indications of the block signals,particularly the caution signal. One way of maintaining such vigilanceis to penalize the engineer each time he allows his train to exceed thepermissive speed limits arbitrarily and automatically established, itbeing assumed that the engineer, in order to avoid such penalty, willkeep vigilant and handle his train safely. Such an expedient formaintaining vigilance is found objectionable in many instances, becauseit is diflicult for the engineer to observe the arbitrary speed limitsfor all blocks without special manipulation. Obviously any penaltyimposed should be one fair to the engineer and preferably one which theengineer can readily avoid by exercising ordinary prudence and care inthe handling of the train.

In view of these considerations, it is proposed in the present inventionto provide a penalty which the engineer may avoid in either of two ways,namely, maintaining the speed of histrain at all times below thearbitrary speed limits, or prior to exceeding such abitrary speed limit,manifesting his vigilance by initiating a brake application,

way and so long as alert and vigilant may readily avoid the penalty. Inorder to be sure that the engineer is alert and vigilant, it is requiredthat he must take the appropriate action before any automatic bra 0application or other operation occurs, othc wise the engineer mightbecome careless and wait until. he :lclt the brakes being applied.before acting to forestall the penalty.

To facilitate the explanation of these fea tures wherea regular tullservice brake application initiated at the block signal or correspondingcontrol point, at which the cam is started, will not maintain the speedot the train below the pern'iissive speed limits, it the train entersthe block at its nori'nal running maximum speed, let us assume a train,running its normal speed of about (59, miles per hour, enters the blockI, and suppose for the first set or conditions that the, cngineerisasleep, neglecttul, or otherwise fails to take appropriate action inobedience to the cantion signal. Asthe train continues at the maximumspeed limit prescribed by the cam, the speed-distance contacts 6163open, and decnergizethe electi.'o- )neumatic valve; and since this valveis energized by a stick circuit, once decnergizcd, it remains dcencrized until picked up by closure of contacts (St-65 at a speed of 2 milesper hour, or substantially stop. In short, it the engineer is negligent,an automatic brake application occurs; and the train nu'lst be broughtto a substantial stop before the brakes an be released and the trainproceed. This constitutes the penalty for lack of vigilance.

Suppose, however, that the engineer sees and recognizes the cautionindieatirm oi the block signal at the entrance to the block I,

and realizing the high speed at which his train is traveling, moves thehandle oi? his regular engineers brake valve to the service position forthe purpose of applying the brakes, this movement of the bra kc valveoccurin before the permissive speed limits are exceeded. So lon as theengii'ieefs brake valve is in the ,1 ice position, it is obvious thatthe brakes are being applied at the service rate as rapidly asconsistent with safety and as rapidly as can be suitably done by anyauton atrc brake applying device. In other words, the engineeids manualaction tends to slow down the train as efiectively as an automatic application ot'the brakes. The engineer lnrs n'lanijlested in this way hisA ance, and the penalty maybe suppressed. It is not necessary in theinterests of safety to have the brakes fully applied at the instant thepermissive speed limits are exceeded, since these permissive speedlimits are se lected and set up on the assumption that the starting of abrake application at that particular point and speed will bring thetrain to a stop at the desired point. r-Xcco-rdingly, it is suflicientit the engineer gets his brake his brake valve out of the service valvein the service position before exceeding the speed limits, the timetaken to get the brakes fully applied being no longer than that requiredfor an automatic application, and due allowance for this time is made indetermining the permissive speed limits.

Applying these principles to the specific system shown in Fig. 2, if theengineer is vigilant and puts his brake valve in the service positionbefore the speed contacts 6163 open, the contact fingers 114 are bridgedby the segment 67, thereby completing an auxiliary stick circuit formaintaining the valve EPV energized independently of its control. by thespeed contacts G2-68, as follows Beginning at .15, contacts 61-114,wires 115 and 112, contacts 7172, wires 113 and 101, winding of thevalve EPV, wires 102 and 10?), front contacts 104; of the EPV and wire105 back to the other terminal C of the battery.

It will be observed that the engineer must move his brake valve to theservice position and close contacts 67114 before the valve EPV isoperated,otherwise the front contacts 104 of said valve are open andinterrupt the auxiliary stick circuit above traced. Hence, the engineercannot wait until some automatic operation occurs before acting In theordinary type of air brake system contemplated by this invention, thebrake pipe is vented by the action of the equalizing discharge pistonvalve responsive to pressure in the equalizing reservoir. The engineersbrake valve exhausts the pressure from the equalizing reservoir, and thebrake pipe pressure .in time assumes a corresponding pres sure, thelength of time required to vent the brake pipev varying with. itsvolume, i. e. length of the train. In the ordinary brake equipment afull service application is made by about 20 pounds reduction; and theengineer may reduce the pressure in the equalizing reservoir about 20pounds by keeping his brake valve in, the service. position for 6 or 7seconds. It is unnecessary to exhaust the equalizing reservoir pressureany lower than this, otherwise there is a waste of air in blowing downthe brake pipe pressure more than required to give a full serviceapplication, It frequently takes a much longer time than 0 or 7 secondsto stop the train; and to avoid this waste of air, the timing mecha--nism CM is employed; so that if the engineer has kept his brake valve inthe service position for 6 or 7 seconds (long enough to make the desiredfull service reduction in the equalizing reservoir pressure) the timingmechanism will serve to maintain the valve EPV energized and theengineer may then move position to the lap position. i

When the engineer moves his brake valve to the service position toinitiate the control of a service brake application, the contact fingers110 are bridged by the contact segment 69 so as to complete a circuitfor the electrically operated valve EV, which is readily traced in thedrawings. V'Vith the valve EV energized, the clockwork mechanism CM isstarted; and. after an interval of 6 or 7 seconds the contacts and 235are closed, whereupon the device EPV is maintained energized throughanother partial circuit entirely in dependent of the speed contacts 61and 63 and the valve contacts 67-114, which may be traced as follows:bcginning at the terminal B, wire 111, contacts 85, wire 112, contacts7172, wires 113 and 101, winding of the EPV, wires 102-103, frontcontact 10%, wire 105, back to the common return wire G.

Since the engineer has held the. handle 66 of his brake valve in theservice position for this period of time (6 or 7 seconds), theappropriate reduction in the equalizing reservoir pressure for a fullservice application is assumed, and he may'move his engineers valve intothe lap position, the electrically operated *alvc EV being maintainedenergized through the following stick circuit :beginning at the terminalB, wire 111, contacts 235, wire 11, contacts 68-117, wire 118, frontcontact 119 of the valve EV, wires 120 and 121, winding of the valve EV,wire 122 back to common return wire C.

If the engineer should attempt to defeat the objects of the invention,and instead of making a full service reduction in equalizing reservoirpressure, should move his brake *alve out of the service position beforethe expiration of the time interval of 6 or 7 seconds, the valve EPV isdeenergized, and thereafter the train must be brought to a substantialstop the bra kes can be released, this assuming of course that the speedof the train at the time in question is above the permissive speedlimit. This result follows from the fact that, as soon as the engineermoves his brake 'alve out of the service position, the contacts 67'114open; and since there has not been time enough for the contacts 85 toclose, both auxiliary stick circuits for the valve EPV are interrupted.Also, if the engineer should attempt to release the brakes while thespeed is excessive after he has made the recpiircd full serviceapplication, the valve EPV is deenergized and the penalty imposed,because in the releasing positions of the brake valve (release orrunning), thecontacts 6711-t are open, and likewise contacts 69110 areopen. The opening of the latter contacts 69 110 dcenergizes the valveEPV and instantly restores the timing mechanism GM to the normal orinitial position, opening contacts 85. Both of the auxiliarystickcircuits for the valve EPV are consequently open.

The contact segments 67, 68 and 69, as shown, are of such length thatthey bridge their corresponding pairs of fingers in the emergencyposition of the engineers brake (2 miles per hour) before valve as wellas in the service position. This is optional but is done'so that, it theengineer makes an emergency application for any reason instead of aservice, the penalty will be suppressed just as well as it a serviceapplication has been made, it being obviously unfair to penalize theengineer for using an emergency application instead of the service ifconditions warrant,

Assume that the engineer has been vigilant and has taken the appropriateactions above described in obedience to the caution signal. As soon asthe speed of the train has been re duced to a value less than, thepermissive speed set up by the apparatus, the engineer may move hisbrake valve into the running or release position, releasing the brakesand proceeding at that speed, as shown by the horizontal dot-and-dashline at the point X in Fi 1, the brake control valve EPV being energizeddirectly through the speed contacts 61-63. Since the second low speedcam is initiated at the point X, the engineer is required to againinitiate a manual brake application before the permissive speedexceeded, which under the assumed crmdit-ion occurs at the point 26, andhe will be required to hold the manual. brake application until thespeed of the train has been reduced to less than 20 miles per hour, torinstance, in order to avoid an automatic brake application and theassociated penalty, after which the brakes may be released and the traincontinue to move into the danger block at this limited speed.

Dam e1- coatlition. lien the train enters the block J assumed to beoccupied by another train, the loop circuit influence receiving coils 19will be deprived of trackway energy and the control relay R will assumeits deen ergized position regardless of whether or not sin'iplex circuitcurrent is flowing in the block J, because the track or loop circuit'current is shunted away trom the train in question by reason of thetrain ahead. Assume now that, with the t "ain in question moving in theblock J, the other train heretofore mentioned moves out of the block Jinto the following block. Under this condition the loop circuitapparatus of the train in question again receives energy from the loopcircuit ahead of the train, and the simplex winding of the relay R acurrent of reversed relative directi on or flow therein, so that therelay R again assu mes the reversed position and permits the Modifiedfor-m of speed c07l-t1' 0Z.-Th'e particular organization of carapparatus shown in Figs. 1 and 2 contemplates two cains governing speedsfrom a high to a medium, and from a medium to a low speed, respectively.It will be evident that the scheme for imposing vigilance whichcharacterizes this invention is not restricted to this particular torinof speed control. For example, only one cam may be used,- establishingspeed limits from an unlimited speed or a maximum down to a low orminimum. In fact, the gradual change in permissive speed limits provided by the cam or cams may be eliminated, if desired; and the systemoperated properly with abrupt changes in speed limit from a maximum to aminimum, or from a maximum to a medium and then to a minimum speedlimit.

Double-beadiag.1n hauling heavy trains it is frequently necessary tocouple two or more locomotives in the same train. Ordinarily this isdone by "double-heading that is, coupling two engines together at thehead. of the train. The air brake equipment for locomotives or the usualtype is such that, when two locomotives are coupled together in a train,it is necessary for well-known reasons to close avalve between the mainengineers brake valve and the brakepipe, commonly called thedouble-heading cock, on the second or other locomotive in the train inorder that the brakes on this helper locomotive may be applied andreleased fromthe leading locomotive the same as if the helperlocon'iotive was a car. in g cock commonly found on all engineequipment, it is possible for the engineer to cutout the automatic brakecontrol, that is, eliminate the functions of i the automatic brakeapplying mechanism which is set into operation by the deenergization ofthe valve EPV. This is true whether the v'alve EPV controls an actuatorfor the regular engineers brake *alve or- "an additional brake applyingvalve, inasmuch as the connections to the brake pipe should be nia deabove the doubleheading cock, otherwise the brakes will be applied onthe train automatically I upon exceeding the n'linimum speed limit,because the helper locomotive is unable to pick up track or loop circuitcurrent. In short, by closing the doubleheading cock the engineer mayavoid theautomatic application.

Referring to this invention, it Will be evi dent that if thedouble-heading cock has been closed, the engineer may put his brakevalve in the service position for 6 01-7 seconds without applying thebrakes in so doing; *et so far as the control or the EPV heretoforedescribed is concerned, such manipulation would. serve to maintain thevalve EPV energized and suppress the penalty. As previously explained,however, it is one of the principles or this invention that the engineerOn account of this double-headshould not be able to suppress the penaltyeXcept by actually applying the brakes; and to assure that thedouble-heading cock cannot be used, together with the manipulation ofthe engineers brake valve, to suppress the penalty. the double-headingcock 70 is provided with a contact segment 71 bridging contact lingers 72 only if said double-heading cock is open, these contacts being open ifthe double-heading cock is closed. These contacts 71-72, it will benoted, are included in the auxiliary energizing circuit for the valveFPV. Consequently, if the engineer should close the double-heading cock,these contacts 7172 are opened by this movement, and it is not possiblefor the engineer to maintain the valve EPV energized and suppress thepenalty. 13y reason of this penalty, it is considered that the use ofthe double-heading cock to forestall automatic brake application will bediscouraged, it being much easier to make a brake application in theregular way and forestall the penalty.

Modificdpcn-altg suppressing means (Fig. 3

In Fig. 3 has been shown a portion of the car-carried apparatus of asystem, such as shown in Figs. 1 and 2, in which the clockwork mechanismcircuit is somewhat simplified by reason of a change in the circuitarrangement resulting from the fact that the device EPV and the valve EVhave their windings connected in series at times. In this modifiedarrangement the electro-pneumatic brake applying device EPV has itswinding designed slightly different and is energized by a circuit such.heretofore traced in F ig. 2 which has included therein a resistance124.

This resistance 124 is substantially the same winding of the valve EVand not the resist ance 124.

In this penalty suppressing arrangement the device EPV is maintainedenergized independently of its control by the speed control mechanismwhen the engineers brake valve is in the service position through thefollowing circuit :beginning at the terminal B, wire 125, contacts126127, wire 128, winding of the-device EV, wire 130, contacts 71 72,wires 113 and 101, winding of the EPV, wires 102, and 103, front contact104 of the device EPV, wire 105, back to common return wire C. Thecircuit just traced not only maintains the brake applying device EPVenergized but also actuates the electrically operated valve EV therebycausing the contacts 85 to be closed after a predetermined time (0 or 7seconds) by reason of the clockwork meuimnism CM shows, in. Fig. 2.

Modified penalty suppressing means (Fig. .4).

In the systems thus far described the penalty suppressing means becomeseffective as soon as the engineer moves the brake valve to theserviceposition, and remains effective providing he leaves it there for atleast 6 or 7 seconds. In certain railway systems it is deemed practicalto require the engineer to maintain the engineers brake valve in theservice position as long as the speed of the train is excessive; and inFig. 4 has been illustrated a penalty suppressing relay PR which makesit possible for the engineer to suppress or avoid the penalty providinghe moves his brake valve to the service position before an automaticbrake application is initiated and keeps it there.

In the system shown in Fig. 4 (portions thereof being omitted) thedevices used are the same those shown in Fig. 2, except that there hasbeen added an additional contact 138 to the brake applying device EPV,and speed contacts, comprising contact fingers 139, which are closedwhen the speed of the train isless than 22 miles per hour.

Assume that the permissive speed is gradually decreasing and the speedof the train is such that it is just about to exceed the permissivespeed limit. If now the engineer moves his valve to the service oremergency posit-ion before the device EPV is deenergized, a pick-upcircuit for the penalty suppressing relay PR is completed which may betraced as follows :beginning at the terminal B of a battery. wire 137,front contact 138 of the device EPV, wires 140 and 141, winding of thepenalty suppressing relav PR, wire 142, contacts 126127, wire,

143, back to the common return wire C. lVith this circuit completed therelay PR picks up and completes a stick circuit through its frontcontact 144 which may be traced as follows :beginning at the terminal B,wire 145. front contact 144, wires 146 and 141, winding of the relay PR,wire 142, c011- t'acts 126127, wire 143, back to the common return wireC.

It now the speed of the train exceeds the permissive speed set up by thecam 39, an automatic brake application will be initiated by the deviceThis application may iii however be ineltectual since the auxiliaryreservoir has already been partially vented by manual movement of thebrake valve to the service position; Even though the device EPV hasassumed its deenergized position and has opened contacts 138, thepenalty suppressing relay PR is nevertheless maintained energizedthroughits stick circuit including contact 144;, so long as the engineers valveis kept in the service position. As soon as the train speed has beenreduced to 22 miles per hour, contacts 139 are closed and the device EPVis picked up through the itollowing circuit :-beginning at. the terminalB, wire 100, contacts Gland '3, wire 101, winding of the device EPV,wires 102-l06 and 1&7, contacts 139, wire 148, contact 149, wire 150,back to common return wire C. After the device EIV is once picked up, itwill again be stuck up through its stick circuit including contact 10 solong as the permissive speed setup by the cam is not ex ceded.

lad the engineer put his brake valve in the serviceposition after thebrake applying device EPV was deenergizcd in response to excessive spce.l,'the penalty suppressing relay PR could not have been picked up,because the pick-up circuit including the. contacts 138 was not intact,and consequently a penalty would have been inflicted requiring theengineer 'to reduce the speed to less than 2 miles per hour before thedevice EPV could have again been picked up. Reducing the speed to 2miles per hour causes closing of contacts (k and 65 and ener'giZation ofthis device EPV. In otl'i'er words, in the arrange- 1ncnt shown in Fig.4 the engineer, it alert,

may anticipate the automatic actlon by a.

partial or co'mplete manual brake application, and by so doing ispermitted to release the brakes as soon as the speed is less than 22miles per hour; whereas it he fails to anticipate the ai'ito'n'i'aticaction he is penalized by being required to bring the train to a lowspeed of, say, 2 miles per hour which practically corresponds to a stop.

In the arrangement of Fig. at, whenever the train exceeds theperm'issivespeed limits, the'engineer must keep his brake Valve in theservice position until the train has been brought down to a low s1ieed,'assumed to be .22 miles per hour, Keeping the brake "valve in theservice position for a11'el.\'ten'ded period of time may result in anunnecessary reduction in brake pipe pressure; but in some cases andunder some circumstances, this may not be objectionable, the train 1158- 'que'i'itl' being braked down to a speed less than a suitablecontrol speedpsuch as 22 miles per hour, be'tore the brake pipe has beenmaterially over reduced.

[Manama systems; ,descv'dptz'oa f Fig. particular Track/wagapparatus.The

type of intermittent system to which the penalty suppressing meansembi'idying the present invention has been shown applied is one of thetime-distance interval type. This system includes track elements fortransmit. ting control influences to the car-carried apparatus of whicha pair ol such elements is used to transmit two successive impulses inless than a certain time if the speed of the train is excessive asdetermined by the spacing of such pair of elements. In order to simplifythe disclosure of the system shown in Fig. 5 only one pair of a seriesof pairs of track elements has been illustrated, this pair being shownat the exit end of the block M, one element of which is controlled bythe track relay l of the block N next in advance, the

other element of this pair being permanently.

active.

The first element of each pair comprises a U-shaped core 152tern'iinating in enlarged pole pieces 153 preferably constructed ot ahigh grade of laminated magnetic material. The second'el'ement of eachpair comprises a similar core having a winding l thereon which isnormally closed in a circuit of low resistance by the tront contact 155of a line relay 156 which is energized when the block next in advance isunoccupied.

Oar-carried rcZays.The car-carried ap pa'ratu's shown in Fig. 5 includesa group oil sensitive and quick acting relays CR, RR and BB. Theserelays are of the tractive ar 'n'ature type and include wellbalancedlight armatures pivotally supported about a vertical axis so as to makethem immune to jars and vibrations and causes them to respondto smallmomentary changes in the flow of current therethrough. Since theserelays may take any one of various forms as long as they are quickacting and innnune to vibrations they have been shown conventionally,and are provided with contacts con structed and insulated so as toserve; the purpose for which they are intended and as more clearlydescribed in the operation of the system.

Time elem-eat (Zeo'z'0e.In order to apply the brakes of the train by thedeenergization of the electro-p'neumatic valve EPV when twosuccessivecontrol influences are received in less than a certain time, asuitable time element device is required. In the particular embodimentoi the invention illustrated this time element device TE has been showndiagrammatically. This time element de vice essentially comprises abalance wheel 15S which is nominally held in the position shown in thedrawings by the time starting magnet TM in opposition to the bias of aspring 159 having its one end "fastened to the shaft 160 and the otherend to a pinion 161. This time element device TE is so constructed "thatif the timing magnet TM is momentarily deenergized the balance wheel 158will move in a counter-clockwise direction through an angle ofsubstantially 240 as shown by the dotted position of the contacts 162and 168. If the timing magnet TM was deenergized for some time, thebalance wheel 158 would finally assume an intermediate positionsubstantially 120 toward the left of the normal position. In order torestore the time element device to its normal position when it assumessuch an intermediate position, a suitable pneumatically operatedrestoring device has been provided.

Time element restoring cZe ve'ee.T'his restoring device comprises a rack165 in engagement with a pinion 161 and adapted to be operated by apiston 166 contained in a cylinder 167 and urged to the extreme righthand position by a compression coil spring 168. An electrically operateddevice ED, which is constructed substantially identically to that of thedevice EV of Fig. 2, is provided to restore the time element device TEand certain other devices to their normal position or condition as moreclearly pointed out hereinafter.

Speed responsive (Zem'0e.ln connection with the train control system asshown in Fig. a speed responsive device which in dicates the actualrunning speed of the train at any time is required. In order to simplifythe description of the system, a speed governor G of the samecentrifugal type shown in Fig. 2 has been illustrated. This devicegoverns the position of a multiple contact speed arm 169 which isadapted to close various circuits under various existing speedconditions, as more specifically pointed out hereinafter.

L /stem wider nownal e0nttizfiona-Under 4 normal clear traflicconditions of the carcarried apparatus, the control relay CR isenergized by a circuit which may be traced as follows Beginning at theterminal B of 175, back to common return wire G. This car element Lcomprises a U-shaped core of magnetic material similar to that of thetrack elements heretofore described, but arranged in inverted relationand adapted to cooperate with such track elements. lVith the controlrelay CR energized, the repeater relay R1 and the brake control. relayBR are maintained energized through. the following two circuits (1)beginning at the terminal B, wire 170, front contact 171, wires 176 and177, lower winding of the repeater relay RR, wires 178 and 179, frontcontact 180, wire 181, back to common return wire C; and beginning atthe terminal B, wire 170, front contact 171, wires 176 and 182, upperwinding of the brake control relay BR, wire 188, back to the commonreturn wire C.

lVith the repeater relay Bit and the brake control relay BR energized, acircuit for energizing the timing magnet TM may be traced as follows 2-beginning at the terminal B, wire 18-1, front contacts 185 of the brakecontrol relay BR, wires 186 and 187, winding of the timing magnet TM,wire 188, front contact 189 of the repeater relay RR, wire 181, back tocommon return wire C.

With the brake control relay BR energized and the time element deviceenergized and in its normal position as shown, a stick cir cuit for thisbrake control relay through its lower winding may be traced as followsbeginning at the terminal B, wire 18 1, front contacts 185 of the brakecontrol relay BR, wires 186 and 192, contacts 162 of the time elementdevice, wires 193 and 194:, lower winding of the brake control relay BR,wire 195, back to the common return wire C.

With the brake control relay BB. in its energized position, a circuitfor energizing the primary coil P of the car element L and thec.cctro-pneumatic brake control device EPV in series may be tracedfollows beginning at the terminal B of a suitable source of energy, wire196, front contact 197 of the brake control relay BR, wire 198,resistance 199 (used for reasons hereinafter described), wires 200 and201, primary coil 1, wire 202, contact 203 operated by the rack 165,wire 20 1, winding of the device EPV, wires 205 and 206, front contact228 of the EPV, wire 229, back to common return wire G.

lVith the primary coil P of the ear element L energized by the circuitjust traced, a certain magnetomotive-force is set up in the core of thecare-lenient L which causes a certain. amount of flux to pass throughthe primary coil P. This flux, it is believed, passes to a large extentthrough leakage paths which do not include the secondary coil 0',

so that, if this car clement bridged by an active track element, thedistribution of flux emanating from the leg containing the primary coilP is changed to produce a change of flux in the secondary coil S.

Operation.

relay 156 and putting the core 15% of the secondtrack element of thepair in an open circuit. As the train moves through the block 'N andreaches the first track element of the pair illustrated, the passage ofthis car element L over this track element causes a sudden increase offlux through the secondary coil S and then a sudden decrease of flux,whereby an alternating wave of elec tro-motive-t'orce generated in thesecondary coil corresponding to that of a single cycle of alternatingcurrent. l he secondary coil S is preterably connected .in the circuitot' the control relay OR in a manner so that the first wave of voltageinduced therein opposes'that of the voltage of the battery energizingthe control relay CR, so that the control relay (JR is momentarilydeencr gizcd. This cycle of alternating current voltage induced in thesecondary coil S is, it is believed, due to a large extent to diversionof flux from leakage paths through the secondary coil. S and to acertain extent to an increase in the total tlux passing through theprimary coil P. The momentary deenergization of the control relay CRpermanently deenergizes this relay because its stick circuit includingthe front contact 1'71 is ln'oken.

With the control relay CR dcenergized, the repeater relay RR isdeene'rgized, and since this repeater relay ER is also connected in astick circuit including its own contact 180, it is permanentlydeenergized until restored by some other means. lVit-h the repeaterrelay RR deenergized, the circuit for energizing the timing magnet TM isbroken and the time element device TE starts on its cycle of operation.Before, however, the time element device TE has operated far enough toopen its contacts 162, the back contacts 207 of the repeater relay RRcloses a pick-up circuit for again picking up the control relay CR whichmay be traced as follows: beginning at the terminal B, wire 18 1,contacts 185 of the relay BR, wires 186 and 192, contacts 162 ot thetime element device, wires 193 and 208, backcontacts 207 oi the repeaterrelay RR, wires 209, 210 and 173, winding of the control relay CR, wire174-, secondary coil S, wire 175, back to the common return wire C.After the control relay CR has been picked up in this manner it is againin condition jto maintain. the brake control relay BR energized throughthe circuit heretofore traced, this brake control relay BE in themeantime having been held up by the circuit including the contact 162 ofthe time element device.

It shouldbe remembered that at the pa rticular stage in the cycle ofoperation just described the control relay GR is again picked up but therepeater relay is still in its deenergized position, the brake controlrelay BR being now held up by the control relay CR alone and not also bythe circuit including contact 162 of the time element device. When thetime element device swings in a countencloclc wise direction, thecontact 163 of this device during the last portion of its strokecontacts with the stationary contact 5211 and completes a pick upcircuit for the repeater relay RE which may be traced as followsbeginning at the terminal B, wire 170, front contact 171 of the controlrelay CR, wires 176 and 177, lower winding of the relay RR, wires 178and 219., contacts 211-163, wire 213. back to the common return wire G.Since, as has been assumed, the speed of the train not excessive, thetime element device TE will. complete its cycle and return to its normalcondition before the car passes by the second track element of the pair;this time element device being held in its normal position by the timingmagnet TM, this magnet being energized because the repeater relay RE- isin its picked up position.

Assume that the train now passes over the second element of the pair oftrack elements, the time element device again starts from its inactiveposition and completes a cycle of operation in the same manner as justeX- plaincd without imposing a brake application.

Caution. condition (speed excessive, enginccr n01 alert) .Let us assumethat the train in ques ion passes by the first element of the pair oftrack elements in the block M, when the next block in advance isoccupied by an other train, and that the speed of the train isexcessive. The passage of the train by this first element initiates thetime element device TE for reasons heretofore given, so that this timeelement device has only partly completed its cycle of operation when thecar element L passes over the second track element, which now has itscoil open-circuited. As the car element passes over the secondtrackelement, the control relay GR is deenergized as here to'l'oredescribed. Since the time element device TE has already started on itscycle of operation, the contact 162 is open and theretore deenergizationof the control relay CR- deenergizes the brake control relay BR, so thatthe trout contacts 185 of this relay BR open and thereby prevent thetime starting magnet TM from again being energized and the control relayCR from again being picked up. The deenergization'otthe brake controlrelay BR also interrupts the stick circuit for the brake applying deviceEPV as heretofore traced, thereby causing an automatic application ofthe brakes and the stopping of the train, the engineer being unable torestore the device EPV until a penalty has been inflicted which, in thepresent system, consists in requiring him to reduce the speed to lessthan. 2 miles per hour.

The time element device TE and the various relays may be restored by theoperation of the time element restoring rack 165, which is operated inrespo to theenergization of the electroa'esponstvc device ED, W11

217, winding of the device El), wire 218, back I 151 it and will assumetheir deenergized poto common return wire C. Energizat-ion of thisdevice ED permits the flow of air pressure into the c linder 67 causimthe rack to be operated to the left, thereby returning the balance wheel158 to its normal position, and completing the two following pick-upcircuits :(1) beginning at the terminal B, wire 220, contact 203, wires221, 210 and 173, winding of the control relay CR, wire 174, secondarycoil S, wire 175, back to common return wire C; and (2) wire 220,contact 203 on the rack 165, wire 222, upper winding of the repeaterrelay RR, wire 223, back to conunon return wire C. With the controlrelay Cit and the repeater relay l-R energized and the time clementdevice TE in its normal position, the brake control relay BB is pickedup, sothat a pick-up circuit for the brake applying device EVP iscompleted as soon as the push button 224 is released and. the rack 1G5and its associated contact 203 has re-' turned to its normal positionproviding the speed of the train is less than 2 miles per hourgwhichcircuitcomprises the normally energized circuit for the device EPV tothe winding of this device from whence it comcpriscswires 205 and 225,contact 226 of the in thismanner may release the brakes and againproceed along the track in accordance with tra'tlic conditions ahead.The push button is used to avoid unnecessary operation of the timeelement restoring device every time the train stops.

Caution condition (speed excessioe, engincer (m ficipaz es automaticapplication) .In view of the foregoing operations of the system shown inFig. 5 as described, it is of course:

understood that, if the train moves at a speed to receive two successivecontrolinfiuences in less than a predetermined tune, the relays CR,

sition and the time element device TE will assume its intermediateposition. Let us assume now that the engineer has moved his brake valvehandle 66 to the service brake ap-' plying position before he passes apair of spaced elements at excessive speed and the brake control relayBB- is deenergized. Since, under this condition, the brake controldevice EPVis still up and its stick contact is still closed, aenergizing circuit forthis device EPV and theelectrically operated valveEV'of the clockwork mechanism CM heretofore described in connection withFig. 2 in series is completed and may be traced as follows beginning atthe terminal B, wire 230, contacts 231 wire 23?), winding of the deviceEV, wires 234 and 201, primary coil P, wire 2 02, contact 203 operatedby the rack 165', wire 20%, winding of the device EPV, ircs 205 and 206,front contact 228, wire 229, back to common return wire C. Sutlicientcurrent is caused to flow in the branch including the electricallyoperated valve EV as distinguished from the branch including theresistance 199 by reason of the relative value of the ohmic resistancesof thesetwo branches, and the resistance 199 has been added for thepurpose of dividing the current for the primary coil P and the deviceEPV in series between. these two branches in such a way that the deviceEV responds when the brake valve is moved to the service position. Thiscircuit maintains the brake ap-. plying device EPV energized andinactive and also starts the clockwork'n'iechanism CM described inconnection with Fig. 2 so as to close the contacts and 235 apredetermined period of time after the brake application has beenstarted (assumed to be 6 or 7 seconds); It is thus noted that theengincecr may procoed along the track without getting an automatic brakeapplication even though "the speed restriction set up by the spacing of:track elements along the track has been exceeded, providing he hasanticipated such an automatic brake application byplacing his brakevalve in the service position and keeps it there long enough to make aneffective manual application of the brakes and providing he keeps thebrakes applied until the speed of the train has been reduced to 22 milesper hour as indicated by the governor G, If the engineers brake valvehas been held in the service position for the predetermined timementioned, that is, until the contacts 85 are closed, he may move thebrake valve to the lap position, whereupon a circuit is closed includingthe device EVand EPV and the following partial circuit beginning at theterminal B, wire 236, contacts 237-238, wire 239, contacts 85, wires24:0 and After the speed of the train has been reduced to less than 22miles per hour, the re lays CR, RR and BB and the time element device TEmay be restored to their normal condition by the depression of pushbutton 224 which energizes the restoring electro-responslve device EDthrough thefollowing circuit beginning at the terminal B, wire 241, 7contact 2420f the speed governor G, wire 243,

contacts 235, wire 24st, push button 224-, wire 217, winding of thedevice ED, wire 218, back to the common return wire, C. lVith the restorng device ED energized, the time element device and other changed partsmay be restoredto itsnoimalcondition, so as to allow the train toproceed in accordance with traffic conditions ahead: It should be notedthat even though-the automatic brake con trol mechanism has beenactuated no penalty (reduction ofspeed to less than 2 miles per hour)has been inflicted, because the engineer has anticipated-the automaticbrake applica-- tion by a full service manual brake appliczn tion.

that the train inquestion passes by thepair of track elements ata speedin excess of that permitted by the spacing of these elements -wlicn theblock N- is occupied; Under this condition ,the time element device TBis initiated on its cycle oi operation when the train passes by thefirst elemen t for reasons heretofore given. \Vhen the car element Lpasses by the second track element, even 'though the time element devicehas not 'yet returned to its normal condition no automatic brakeapplication takes place. This is because the second element is notcapable of'transmittinga control influence when its windingl5 lisclosed'in'a'circuitof low resistance. One theory of reasoning by whichthis immunity of 're'sponse'of the car element words, the-winding 154 onthe track elementv acts, itlis believed, as a bucking coil, therebypreventing a material change of flux through the secondary coil of thecar element L even though it is disposed in cooperative relation with amagnetizable core 152 of low reluctance. It is thus noted that only onecontrol influence is transmitted from each pair of track devices underclear traffic conditions of a block so that no'speed restriction is setup by these pairs of elements.

Modified penalty suppressing vnetms.

In Fig; 6 of the drawings has been illustrated a system substantiallythe same as that shown'in Fig. 5 (certain parts thereof being omitted)vin which, the penalty suppressing means includes a" penalty suppressingrelay PR substantially the same as that shown in Figgt'requirmg theengineer to anticipate an automatic brake application and requiringhimto keep his brake valve in the service position until the speed ofthetrain has been reduced to, say, 22 miles per hour in order to avoidthepenalty of practically coming to a stop. In the embodiment of theiIlVGlltlQll' shown in Fig; 6, ii? the engineer moves hls brake valve tothe service position, a circuit is completed-for picking up the penaltysuppressing relay PR which may be traced as follows z-beginning at theterminal B, wire 196, front contact 197 of the brake control relay BR,wires 1.98 and 234:, wire 24G, winding of the relay PR, wire 247,contacts 2 i8-2-i9, wire 250, back to common return wire C.

iVith the relay PR in i ts energize-d position, a stick circuit forthisrelay is completed as followsz wire 251, front contact 252 of thepenalty suppressing relay PR, wires 253 and 2-l(i, winding of the relayPR, wire 247, contacts 2t8-2 l9, wire 250, back to common return wire G.Also, with this relay energized, another circuit for holdingthe deviceEPV in its energized position-is con'ipleted which maybetracedas-follows beginning at the terminalB, wire 251, front contact 252of the relay PR, wires 253, 234and'201, pri'l'nary coil P, wire 202,contact 203 operated by the rack 165, wi re 204, winding of the EPV,wires 205 and 206, front contact 228 of'the EPV, wire 229, back to thecommon return wire C.

It is thus noted that the train may proceed along the track without theimposition of anaut'omatic bral-Ie application. even though the speedset up by' the spaced track elements is exceeded under caution. trafiicconditions, providing the engineer has anticipated such an applicationby initiating a manual appli- "at ion. At'terthe speed of'the train hasbeen reducedto 22 miles per hour under the conditions just mentioned,the time-distance brake applying mechanism maybe restored to its normalcondition by the engineers operation of the push button 22st, by reasonof which the following circuit is completed beginning at the terminal B,wire 254, front contact 255, of the relay PR, wire 256, contact 242,ot'the governor G, wire 244, push button contact; 224-, wire 2l7,winding of the device ED, wire 218, back to common return wire C. Thecompletion o't this circuit returns the time-distance interval brake apiilying mechanism to its normal position, thereby permitting the trainto proceed in accordance with traffic conditions ahead as soon as therack returns to its normal position.

lVhile'several specific forms of the invention'have been shown anddescribed, and the invention has been applied to speed.- control systemsboth the continuous inductive control type and. the intermittentinductive control type based on the time-distance interval principle, ineach form the primary purpose is to stimulate and maintain vigilance onthe part ofjtheengineer, and requiring him un-- derpenalty of beingobliged to stop-in order to proceed, to recognize and observe theinclications of the block signals, particularly the plication isinitiated. Various penalty suppressing means have been provided forsuppressing the penalty in accordance with various degrees ofrefinement. The first one of these permits the engineer, afterinitiating the brake application, to put the engineers brake valve backinto the lap position, Whereby excessive venting of the brake pipe isprovent-ed. This is desirable, so that a corresponding small. amount ofair pressure only need be pumped into the brake pipe when the brakes areagain released. In the second mentioned penalty suppressing means theengineer is required to keep his brake valve in the service positionpermanently until the speed oi the train has been reduced to a satevalue, which has been taken at 22 miles per hour.

Having thus shown and described several embodiments of the invention asapplied to several diili erent types of train control systems, thespecific disclosures made have been shown to illustrate the nature ofthe invention rather than its scope, and it is desired to be understoodthat various changes and modifications may be made to adapt theinvention to various other types of systems without departing from thespirit of the invention or the idea of means underlying the same.

lVhat I desire to secure by Letters Patent of the United States is 1. Inan automatic train control system, the combination of means on the trainfor applying the brakes in the usual air brake system, means for settingup permissive speed limits for the train, penalty means if efiectiverequiring the train to be stopped each time the brakes are automaticallyapplied before the brakes can be released, and means including a timeelement device superimposed upon said usual air brake system forpreventing said penalty means from becol'i'iing effective and active ifand only it the brake valve is in the service position or has been thereat least long enough to cause a predetermined degree of brakeapplication since the last time the train brakes have been released.

2. In an automatic train control system, the combination with the usualair brake system including means for applying the ed to the engineersbrake valve and effective 1t and only it the brake valve is in theservice position or has been there a period of time equal to or morethan that necessary to cause,

a predetermined reduction in the equalizing reservoir pressure of saidair brake system and has not thereafter been moved to a brake releasingposition.

3. An automatic train control system comprising, an automatic brakeapplying device superimposed on the usual type of air brake systemincluding the usual charged brake pipe, means for automaticallyactuating said device if predetermined. speed limits are exceeded, meanstor penalizing the engineer it similar speed limits are exceeded, and.means for preventing the infliction of a penalty by said last mentionedmeans including a time element device operatively connected to theengineers brake valve of said system effective if the engineers brakevalve has been in the brake applying position for a period of timecorresponding to the time necessary to initiate an adequate brake apiiliciu'ionand has not been returned to the brake releasing positionthereafter.

4. In an automatic train control system, the combination of means forautomatically applying the brakes ot the usual. air brake system of atrain, and means for preventing such an automatic brake applicationincluding a time element device separate and distinct from the air brakesystem itself but governed by the engineefls brake valve which iseffective to prevent such brake application a predetermined time attersaid time elen'lent device has been initiated and providing theengineefisbrake valve has not therea'ttcr been moved to the running orrelease position, and

means for initiating said time elen'ient device effective it and only ifthe engineers brake valve is in the brake applying position.

5. In an automatic train control system, the combination of meansfor-automatically applying the brakes ot the train it the speed of thetrain is excessive, means for penalizing the engineer if the speed ofthe train is excessive, and means including a time element device inaddition to the usual air brake system governed by the engineers brakevalve for suppressing operation. of said penalizing means effective ifand only it the usual engineers brake valve is in the brake applyinposition or has been in such position tor a predetermined time and hasthereafter not been moved toward the brake releasing position beyond thelap position.

6. In an automatic train control system of the time-distance intervaltype, the combinaot' a normally energized and normally inactive brakeapplying device, a penalty in dieting device, means partly on thetrackway and partly on the vehicle for transmitting control influence tothe car-carried apparatus and including trackway devices spaced inaccord-

